NEW YORK -- In a courtroom surprise, it was revealed Tuesday that Bernard Madoff will plead guilty Thursday to securities fraud, perjury and other crimes, knowing that he could face up to 150 years in prison for one of the largest frauds in history.

The revelation came as prosecutors unveiled an 11-count charging document against the 70-year-old former Nasdaq chairman, and as his lawyer, Ira Sorkin, told a judge that Madoff planned to plead guilty this week without a plea deal.

Madoff has been under house arrest in his $7 million Manhattan penthouse since he was arrested in early December after authorities said he confessed to his family that he had carried out a $50 billion fraud. In court documents filed Tuesday, prosecutors raised the size of the fraud to $64.8 billion, an amount recounted in apparently false statements from November 2008.

Authorities reviewing the finances of Madoff's business say the actual loss was more likely much less and that higher numbers reflect false profits he promised investors. So far, authorities have located about $1 billion for jilted investors.

Sorkin, prosecutors and U.S. District Judge Denny Chin presaged the drama likely to unfold Thursday as Madoff, wearing a gray suitcoat over a black tie, sat quietly beside his lawyers.

Madoff, who wears a bulletproof vest, arrived at court more than three hours before the hearing as authorities tried to diminish the chance he would face a confrontation with investors. Several lawyers for investors showed up as spectators, but the courtroom was largely packed with members of the media.

Asked by the judge if Madoff would plead guilty Thursday, Sorkin said: "I think that's a fair expectation." Chin asked Sorkin if Madoff would plead guilty to all 11 counts.

"Yes your honor," Sorkin answered.

Assistant U.S. Attorney Marc Litt said there was no plea deal and that Madoff could be exposed to the maximum penalty under sentencing guidelines: 150 years.

Chin said he would not sentence Madoff on Thursday, and he would limit investors who want to speak at the hearing to those challenging whether the plea should be accepted or whether Madoff should be allowed to remain on bail pending sentencing.

"There is no plea bargain here. Those victims who objected to a plea bargain no longer have a reason to object," Chin said.

At least 25 Madoff investors have asked to speak Thursday under provisions allowing victims of crime to appear at a plea hearing. Attorney Jerry Reisman, who represents more than a dozen Madoff investors, predicted that the plea hearing would be "a zoo."

"I will tell you my clients are outraged by his being able to escape with a guilty plea," he said.

But Chin told prosecutors to limit the number of victims who will speak in court and make sure they conduct themselves in a "respectful and dignified manner."

U.S. Attorney Lev L. Dassin said in a release that the charges "reflect an extraordinary array of crimes committed by Bernard Madoff for over 20 years. While the alleged crimes are not novel, the size and scope of Mr. Madoff's fraud are unprecedented."

He said in addition to facing 150 years in prison, Madoff will pay mandatory restitution to victims, forfeiture of ill-gotten gains and criminal fines.

He also noted that the government has not entered into any agreement with Madoff about his plea or sentencing and that the filing of the charges do not end the matter.